Have Two More Men Been Cured of HIV?Return to The Insider: News & Views
July 09 2013
Has it happened again? Two men, after receiving stem cell transplants, are showing undetectable levels of HIV.
In 2008, the “Berlin patient,” Timothy Ray Brown, became the first person in the history of this disease to be reported cured of HIV. Brown became HIV-positive in 1996. In 2006, he discovered that he had leukemia. His doctor, Gero Hutter, performed a blood stem cell transplant to treat the leukemia, using cells from a donor who had a rare genetic mutation that made his cells resistant to HIV. Since the surgery in 2007, Timothy Ray Brown has remained cured of HIV.
Now, doctors from Harvard-affiliated Brigham and Women’s Hospital in Boston are reporting similar outcomes after two patients, both of whom were HIV-positive and had lymphoma, underwent stem cell transplants. Years after the surgery, and now months off antiretroviral therapy, the two men are showing undetectable HIV levels. The difference between their cases and that of Timothy Ray Brown is that their donors did not have the genetic mutation that makes cells resistant to HIV. Instead, they remained on antiretroviral therapy during and after their surgery, where Timothy Ray Brown went off antiretroviral therapy immediately after his surgery.
An article in Nature explains how the transplant could protect these men, even if the donor cells didn’t exhibit HIV resistance:
“Their doctors think that an immune response called graft-versus-host disease — a post-transplant reaction in which donated cells kill off a patient’s own cells — may have then wiped out the patients’ HIV reservoirs, potentially curing the men.”
While stem cell transplants are not viable options for an HIV cure, the news from Brigham and Women’s Hospital is encouraging for scientists who are exploring HIV cure strategies. As one researcher, Sharon Lewin, M.D., Ph.D., Department of Infectious Diseases, at the Alfred Hospital and Monash University, and Co-Head of the Centre for Biomedical Research at the Burnet Institute, in Melbourne, Australia, explains:
“…these cases will open up new avenues of research. Can we modify the transplant procedure to eliminate the HIV reservoir but not totally wipe out the patient’s own cells? Could the same result be achieved with some but not all of the complex treatment? Can this outcome be mimicked with a vaccine that activates the patient’s own immune response against the reservoir?”
Researchers here at AIDS Research Alliance welcome the findings from Brigham and Women’s Hospital as they continue to explore prostratin’s effects on the HIV reservoirs, thereby making infected cells visible to the body’s immune system, and exposed to antiretroviral therapy.
“With prostratin, we can activate the latent virus so that it is vulnerable to the patients’ own immune system,” explained AIDS Research Alliance Scientific Director, Stefanie Homann, Ph.D. “This alone is not sufficient to eradicate the viral reservoir. Therefore, we will use a combination approach to support the immune system as it detects and kills the virus-harboring cells.”